Your marriage will be strained at some point.
I don’t care if you and your partner are the perfect match, totally in sync, completely in love… at one point or another, this parenting thing is going to get in the way of what you used to have. You will be tired and grumpy and stressed a lot. Also, one on one time is pretty much non-existent in the first few months (or years) after a baby is born. For mom (or at home parent) it is VERY common to feel resentment towards your partner leaving for work every day- getting to interact with other adults, maybe even getting more sleep. And true for dads too, who feel like they don’t get enough time with their baby and are exhausted after working all day (or night). Remember to put yourself in the other person’s shoes sometimes. Remember to talk to each other. Talk to each other. Oh, and did I mention, talk to each other. Make time for each other, even if it is 5 minutes before you pass out to connect. You are in this together and, I promise, this too shall pass…