A Joint Birthday Party???

I'd give it a try...it's a nice way to split the workload and the cost. Most parties are so crazy anyway that the kids don't really care whose party it is, they just want to run around and have fun. Perhaps consider having two smaller cakes, one for each kid so they have something that is "theirs".

I had a joint party at Pump it Up for my daughter's 4th birthday. We did it because renting a place was expensive. The birthday girls didn't seem to mind sharing the party because they each had different friends and had their own cakes and gifts. I did not know the other mom really well, either. In the end, it worked out okay, but I don't think I would do it again. It ended up costing a lot of money anyway. BUt I think you could find a good way to make things work!

I used to work at a movie theater and one time the place that booked it for us, double booked. It was sheer chaos. The two families knew each other though (ironically) and they decided to both have the parties.

They picked a movie that worked for both of the birthday kids and they each stayed on their own sides of the theater.

I'm not sure I would do it because I'm too much of a control freak - but it worked well for them!

Yes--I have done it--but with a different twist.
In my son's K class, there was a girl that had a very close birthday...my son and her daughter wanted to invite the entire class and the moms were more considering just the boys/just the girls type invites. We each had our party (bowling on adjacent lanes) and the kids all got to see each other but the boys brought presents for my son and the girls brought presents for her daughter. We did separate lunch bills, cakes, etc. but it turned out to be really fun.
Since you will be having both boys and I would assume you are all inviting the same kids, it would be 2 gifts to bring, but I wouldn't mind that--2 birds/1 stone thing.
Just make sure they get their own time to open gifts, etc.

Updated

Yes--I have done it--but with a different twist.
In my son's K class, there was a girl that had a very close birthday...my son and her daughter wanted to invite the entire class and the moms were more considering just the boys/just the girls type invites. We each had our party (bowling on adjacent lanes) and the kids all got to see each other but the boys brought presents for my son and the girls brought presents for her daughter. We did separate lunch bills, cakes, etc. but it turned out to be really fun.
Since you will be having both boys and I would assume you are all inviting the same kids, it would be 2 gifts to bring, but I wouldn't mind that--2 birds/1 stone thing.
Just make sure they get their own time to open gifts, etc.

LOVE this idea. It's sometimes hard for parents to take time out of the weekends to get to bday parties, in addition to everything else going on. A boy and girl in my son's preschool class whose moms are friends just did a joint party for them a few weeks ago. It was fabulous. They did it at a craft place, so it wasn't really gender-influenced at all. Cupcakes for all...you can have a cake at your private family celebration. Personally, if I had the choice of attending one party for two kids vs. having bday parties 2 weekends in a row, I'd definitely choose the single party! Just be sure to sing Happy Birthday to each child separately so that they each have their own moment at the party.

We did a shared party for my five year old and two of his classmates. It was wonderful!! Since it was a party for 3 kids we asked for no presents. His entire class was invited plus a couple extra guests from each child and it was at a bounce place. 3 separate cakes, 3 separate "Happy Birthday" songs and everyone had a wonderful time. My son LOVED his party and sharing it did not seem to detract from his enjoyment at all. In his class there are 8 kids with birthdays from Oct 20 - Nov 30 and there were other joint parties during that time. From the parents perspective so much better to try to attend 3 parties than trying to attend 8.

I guess it would depend on the type of party.

Example. If it were a bounce house party, it would work because then you could split the costs down the middle. Just make sure that both kid's names are on the invitation. If it were at her house or your house, it would be a bit more odd.

Each kid should have their own cake.

Again, the issue would be the splitting of the costs, making sure payments are made, etc.

Not a fan of this. My husband and I have the same birthday and I hate it. Love him, hate sharing!!! :)

we share parties....all the time. Rarely with friends, usually with family.

It's double the fun, especially when the guest list is the same!

i did a joint party for my daughter and a cousin one year. It was ok from the kids point of view but a lot of hurt feelings on the adult end. make sure if you do this that you have clearly spelled out who is in charge of what costs etc. my sister in law and i talked and decided to do the party and split the cost. her idea of her end of the cost was her sons gift. I ended up paying for cake, invites, goodies and food. when it came time to pay up she handed me $10 and said this should cover the cake right. and she thought that was fine. i was mad and still am 25 years later lol.

I think it's a great idea. At the beginning of this school year, my 1st grader was invited to 3 parties, for 3 girls, 3 days in a row. She attended all 3, but the moms were saying that next year they should combine them, since they are all in the same class and invite the same kids. Have you mentioned it to your son to see how he feels about it?

I would perfer a separate party.

I would not mind going to a joint party at all. But I would caution you to always write everything down. Such as who pays for this or that and what the expectations are, for example. What is one of you don't want to open presents at the party, I would hate that. I want to see the kids face when they open their presents. What if she wants to do it at home and you want to rent a facility? who gets to decide, what if they have less money to spend than you do? What if they want to do goody bags, door prizes, and all kinds of expensive things. Who will decide what is actually done or not done.

Okay, this is going to sound a little gender bias...because it is...BUT, they are 5 year olds of different sexes. Are they going to want the same type of party? Yes, you could easily do something that is gender neutral (like the movie idea or bowling, or whatever) but is that something they will be happy with? My daughter is only 4 but is getting into so much more girly type stuff and she has some friends that are boys that are just as much into the cars, trucks, etc. My daughter likes that stuff too but I don't think she'd want her birthday party centered around it.

I agree to talk to your son about it first and see how he feels. I also agree with Mom2KCK that I'm way too much of a control freak for this to happen smoothly! ;) Do you have the same personality type of the other mom? Even if you're not a control freak, you could still but heads on money issues (like one of you thinks it's okay to spend $75 on a cake and the other doesn't type stuff), location, etc.

It's certainly an idea to consider, but if it were me, I'd have to hash out more details before I could even decide it was an option, but again, we've discussed my control issues! ;)

Oh, but from a parent perspective I think it'd be fine to attend a joint party if they were going to be invited to both anyway. People get busy, so it'd be nice to knock it out at one time. I don't know if I'd prefer it, but it would be nice.

killing two birds with one stone is always a good idea. Kids birthday parties are over done (we get invited to at least 10 a year, and it drives me crazy!). If I can show up to one party where there would have been two? fabulous!

I would ask the kids about it if you think you can manage it. If they hate the idea, then don't bother.

Friends have a joint party for their kids, but they're really little. They don't care. They got a lot of similar presents (being the same gender and age). I agree that you need to be VERY CLEAR about who pays for what and what is for which kid. Maybe have the same # of balloons in different colors (like one kid gets 12 blue and one gets 12 purple) so it's even but different. At 5, they'll have their own ideas, so I think give them what will happen (decide ahead cake vs cupcakes, for example) and THEN let them personalize that choice.

I suggest neutral territory, like a park or if you have an indoor party room somewhere. I liked going once for both families, but they were both close friends.

Friend did a joint party for her kids - 4 yr old girl and 1 yr old boy. She did a superhero theme and it worked fine for both. The guest list was mixed genders and the girls loved playing dress up as much as the boys liked being heroes. Again, go back to the kids. You could do a lot of themes with different genders - animals, pirates, clowns, cars, etc.

Another friend's sons are 2 yrs apart to the DAY. They always have a joint party, but like I described above, each boy gets his own thing. If T wants Ninja Turtles and M wants cars, that's what she works with.