It's all dependent on the circumstances though, isn't it?
It's not just about whether you can each have time away, but what impact that would have on your partner and children.
I have a job which involves international travel and I had to return to work when my first baby was 7 months old. On my first day back I was informed that there was a trip involving an overnight stay the following week. Then when my son was 11 months old I had to go on a transatlantic business trip for 4 days, with about 2 weeks' notice. A couple of months later when he was 13 months old I had to go on another transatlantic trip, for 5 days this time. Then I got pregnant again and said no to any long haul travel for health reasons, but I did go away overnight twice to visit my friends, knowing that my husband could cope with one child who was over a year old by this point, but coping with two children would be more difficult so it felt like my last opportunity to do it for a while. For context, we live very close to my husband's family and friends but very far from mine.
He was very supportive of all this. And because he had had to cope with me being away for several nights for work, and had coped just fine, we both knew there would be no issues with me being away for just one night to visit friends.
We now have two children and I would do my utmost to avoid these kinds of trips now, because I know that two children is a completely different ballgame, and the little one won't take a bottle. Luckily, although I am back at work, the clients in North America are no longer my responsibility.
If he had to go away for work, I would facilitate this. But he would also ask his mother to come and help me. If he wanted to go away with his friends, who are all past the stag do stage and now all have young children themselves, this would need to be planned well in advance, but I would also facilitate that. Because I know he doesn't feel entitled to do these things, that he would most likely not even think about doing them, and if he did want to, he would make damn sure that I was definitely OK with it before committing.
It goes without saying that if either of our children were ill or injured just before one of us had a planned trip, we would have to discuss what impact it would have on the other parent's ability to do solo childcare, and the person going away would cancel if necessary.