Before calling me Cinderella’s step mom , please hear me out . Throw away account.

I ( F,26) have been with my partner ( M,40) for about 4 years . Our relationship is complicated. When I met him he was emotionally separated from his wife. He was unhappy and they had stopped sleeping together. When we met it was an instant connection. He would change his schedule for me to be with me. He said he couldn’t end his marriage because of his cultural background ( he is Greek) but in reality marriage was just a sham. After 2.5 years, his wife found out . She went through his phone and saw our messages. She told me to never message him again and he stopped communicating. I was heartbroken . Then 8 months later, he messaged me one night ( late night ) and asked if he could come over . He said he missed me and life had been hell and she was making him miserable . We talked and he stayed for a few hours. After that we started our secret relationship. When his wife found out this time , she kicked him out. He moved in with me now and has his kids ( 4 M, 4 f) every other week.

Here is the issue : I’m pregnant . I’m due September. He promised to take his kids on Disney land trip in July which is close to my due date. He can’t change his date because he already submitted his vacation request and also his ex booked a trip back home that week to see her parents. Plus he doesn’t like to ask his ex for a favour . AITAH for expecting him to change his trip for me? I told him we can all go next year . If we go next year , baby and I can join too.