Hi, my daughter had a similar episode recently. Snotty for about a week and then one day of bad constipation. Prune did wonders for her!
100% either the baby prune puree pouches or get a tin of prunes in prune juice, take all the pips out the middle and then blend the pipless prunes and the juice, I freeze them in large ice cube trays (I have a silicone one that has a lid on it) and then I just defrost a cube when I need it and I find he likes it mixed into his morning weetabix 🙌🏼 always handy to have puréed prunes!!! Xx
Prune purée always works a treat for my boy he gets constipated guaranteed he will go that day!