A year would be good, think that way. Anything less is bad, you just want the least bad option. Your spouse needs you there, your kid needs you there, that's the priority.
Unfortunately you can't know what it will be like until you do it. Some kids and parents need very little help, some need lots - you can't choose what your kid will be like. Anyway, it will be great and fucked up and stressful and beautiful
Oooof heheh