[–] TendiesHitTheFloor 1 points 0 points (+1|-1) ago 

Not true. Our first child had issues with the Wife's milk. Gave her formula one time got sleep finally and we just gave her, formula from that point on. The situations vary like everything else in life.

[–] OneOfTheBoys [S] 1 points -1 points (+0|-1) ago  (edited ago)

Exceptions do not disprove the rule.

Additionly:

Bubs is usually unsettled because it’s simply that time of the night (the dreaded witching hour).

The formula puts them into a deeper sleep because the casein in cows’ milk produces more rubbery curds that sit heavily in their baby’s stomach, taking longer to digest. Cows’ milk also has a sedative effect on a breastfed baby (cause mama cows need their calves to be docile and safe by their sides and not run off), who is used to the more digestible, softer curds of human milk.

If you persist through the unsettled behaviour and forgo the evening bottle, babies will cluster feed until their mum’s breasts are nice and soft and drained, which means they will be producing the fattier milk that helps bubs to sleep

-Source