With our first, who is now 5 years old, we were made to feel like he wasn’t putting on enough weight and they made us put him on formula. This was around three months old. My DW has always regretted this and wished she’d feed him for longer.
We have now learnt to not take to much notice of what the MCN’s say and as long as they are looking healthy and are happy then go with what keeps them that way. Don’t worry too much if they aren’t putting on the weight as long as they are healthy and happy.
My new DD (7month old) has been sleeping all night since she was 6 weeks old (lucky us ), she still breast feed about every 3 hours during the day but would generally sleep from around 8pm until 4.30 and sometimes for 10 or 12 hours. She is now sleeping from about 8pm to 7-8am and has been on formula for about 3 weeks she would have around 4 bottles a day and is having Farex in the morning, pureed fruit for lunch and pureed meat and veggies for dinner.