M.P.
ETA: J B, That might work with grandparents who are reasonable. These aren't. I believe it's not safe to leave their son with them. There is a history of grandparents emotional instability to include some sexual inuendos. I would seriously limit their time in my house.
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I assume you've verbally sympathized with them. That is important to getting them to comply.
If there is a way to block texts, I'd do that. If you xan't block them, ignore them. When they call have your husband answer. Say I know you're upset about this. It does hurt to not see your grandson until Labor Day. I'm also upset because you are not accepting my decision. Please stop calling and texting about this. If you continue, I will not answer the phone. Or whatever you decide.
They know what you're saying. They are bullying you in hopes to change your mind. Your husband could call them and tell them to stop the texts and phone calls. Perhaps tell them that if they continue you won't see them until October.
Because their goal is to beat you down, you cannot convince them with reasons and explanations. Stop trying. Remember this is your decision. You are adults and never have to explain your choices. When we explain, we're giving the idea that if they may be able to change your mind especially when they think the reason is not good.
I would not respond to texts. I would not take phone calls. They are acting like children. What would you do if your 14 yo son badgered you? I've had a teen who kept asking. I told him that if he asked again I would not "hear" him. I then ignored him.This helped.
If you use a cell phone, I think you can block calls. If you don't want to block them, tell them you're only taking calls if they do not bring up the summer. When they start tell them you're hanging up and do it.
They have sucked you in by believing you have to convince them. You are not responsible for their happiness. They have turned this into a drama. Step back and think about what you can do to take the stress off you. Take care of yourselves.
I remember your previous posts. I'm glad you went to your parents. Your husband caved to his parents. They have had success by bullying so they continue. Your husband has to stand firm. Apparently, he thinks he has to do what his parents say. He hasn't made the break from his parents. He still feels he has to please them. Somehow, his parents bring out the child.in him. I suggest counseling might help.
Your in laws are lucky to even be able to see your son. I hope their time with your son is supervised. I think you're more than generous with vist time.
Remember you and your husband are in charge of how you spend your time. I would make it very clear that they have to ask your husband if the time is OK. When they just show up, do not invite them in. Do not try to appease them. Be firm and consistent. I suggest you plan when it's a good time to visit and invite them. You and your husband take charge. It is your time and your house. I don't remember if they stay overnight. If they do, make it clear that you aren't able to have them overnight.Don't give them a reason. Just say, in a calm and respectful way that this is the way it's going to be.
If your husband knew his parents planned to visit you an your vacation and said nothing to you, he's taking the easy way out. He needs a backbone. They weren't invited. Why did you spend time with them? I would've told them I had plans that don't include you. Bye! I would be angry with my husband.
Your husband's need to please his parents is having a serious negative effect on your marriage. I wouldn't stay married if he didn't learn how to have boundaries with his parents. I would not do what his parents want even if my husband allowed them to control his life. I would seriously think about leaving the house with your baby when they come unannounced. If they stay the night, I'd go somewhere else for the night. Your husband has it too easy when he allows his parents to decide how you and your husband spend your time. Let him know you are taking charge of your time. He will be between a rock and a hard place. Sometimes we have to feel consequences before we're able to make good decisions. He's an adult and has the responsibility to keep his family safe. A man/woman leaves their parents to make a new life.
As to the kidnapping threat, I would not answer her. I would be sure he's not left in a spot from which he could be kidnapped. If your husband wants to respond he should remind them kidnapping is a felony and he will press charges.
Summary: stop trying to get them to understand. Don't talk about your decision with them. Don't even listen to them. Your only response should be the repetition of not until Labor Day.