Baby crying in the night

If your baby cries in the night, don't go and see him too quickly, but don't let him cry over ten minutes. Check he's ok, that he hasn't got fever or dirtied his nappy. Talk too him softly whilst keeping him in his cot, so that he gets used to it.
After 2 to 4 or 4 months depending on your baby, he'll generally stop crying in the night, or at least less.
If he persists, don't hesitate sending his father. Hopefully he'll understand after a while that he must sleep!