My GF came down to the boat in
Greece when she was 3 months pregnant. She struggled with the heat and the motion when sleeping, but was fine when we were sailing, even healed over. In the end she had to go home to her parents whilst I delivered my boat to
Turkey.
I'm not sure if my GF would have been any better off on a Cat at
anchor, but if I had AC and stayed in a marina she would have been fine.
Of course your daughter may not have any issues or have completely different probs.
My daughter cam for her first sail recently at 2 months and thankfully she was happy to sleep in the forward
cabin when sailing (flat seas) and was also happy in the
cockpit.
For overnight
sails I have jack lines running along the
cockpit floor and when my daughter is old and mobile enough, we will use them for her as well.