Do you expect your children to be invited?
Are you upset if they aren't?
Would you refuse an invitation if your children could not attend?
It depends. Normally, no I don't. But there was one occasion where I did. We're in Tasmania, the wedding was in Brisbane, I had DS3 who was only a few months old and exclusively breastfed. I also hadn't left the big three children for longer than one night and never whilst I was more than a couple of hours away. DH went to the wedding, I stayed home because leaving the big three (who weren't invited), taking the small one (who was invited - because they knew I was breastfeeding and couldn't leave him) and knowing that there would be much partying and catch ups going on that wouldn't be suitable for a baby, it just wasn't suitable. So I didn't go. I was devastated as it was DH's best mates wedding who was best man at our wedding, but I understood and they understood and it was fine.
When DS1 was just 10weeks old my BIL (childless at the time) was getting married and they had a child free wedding despite myself and my SIL having babies the same age and many of their friends having young babies/children. They allowed children at the reception but not the ceremony. I was a little devastated at the time that I couldn't go, but ultimately, it wasn't a big deal and they understood that I wasn't in a position to go.
Every other wedding I've been invited to, I've attended. A couple have been child free and I was able to leave all of my children with my MIL for a few hours or overnight. And another wedding I was allowed to bring DS3 as he was still breastfeeding/dependent on me for sleep.