Well, it's sort of two fold. Your DH loves this church and it suits him, but he now has a family and it doesn't fit them very well. What I would do is look for churches in your area that have programs for kids - VBS, scouts type programs, etc. See if your children could benefit from the activities offered on other days even if they attend Sunday services with you.
Our church doesn't have a lot of kids in the Sunday School. For a while it was just 2 or 3 kids, but now it's sometimes more. I look for other opportunities for DD as well. She likes the routine in "her" church, but I also want her to experience the big group singalong type stuff, too. IMO, there's no reason not to have more than one resource for spiritual needs.
In the summers, we have packets set up for the volunteers. The regular teachers take the summer off and we do a combined aged class (up to 3rd grade) with a prepared story (we buy the material), an activity and sometimes a video or song. Oriental Trading has a ton of VBS type crafts and ideas. If the teachers just randomly pick a story, what about mirroring the sermon? Many times DD and I will get back in the car (her Sunday School is during church time - she leaves after the Children's Moment) and discuss our "stories".
You could also try having a family fun day to attract people to the church on another day and invite them back for church on Sunday. Or go to places like a farmer's market and see if you can set up a booth and do free kid activities. IMO the best time to do this is late summer and early fall, as families get back into routine. What are good things about your church? Are you multicultural? Maybe you could have a "Taste of" event showcasing the talents and cultures in your church.
Before there were a few more kids, I was considering going PT to my friend's church. I still might, as DD gets older and wants to do things like MYF if there aren't enough kids in our church. I like our church for myself, but my needs are changing with hers. I still attend special services at my friend's church, like their Easter Sunrise Service.
Also, don't discount how other things feed into membership. Like if you don't use a FaceBook page, start doing so. Make at least a post or two a week about events and get members to chime in. Offer an e-newsletter. Make sure your website is clear, up to date, and current in style. If you want young families, that starts with their parents.