Identification matters

Spot the odd one out.

It's the third picture. That male has a white feather on his chest.

How do I know this is a mother squirrel?

See the nipples in the second photo? She is lactating.

Easy one - which tit?

Coal tit and then blue tit.

Hard one - are these the same robin and if so, who?

I don't know the answers. But neither are Mottled Breast; the one I have been referring to (perhaps wrongly) as Tiny, who has missing feathers under her right eye; or the one with a whole load of missing feathers under his or her throat. Nor, patently, are they Bobbit or Tengu... or indeed Tapdance.