Seeing the dates laid out like that, I am certain sure, that is Thomas, the first baby born in 1868...about 18months/2 years old, Mum well on the way with the one born later that year and feeling k nackered. This would fit in with the 1870 hairstyle.
Oooo that hansome chap looks just like the baby to me... the left eyebrow looks just exactly the same...and the lower lip,
if not him, then very close family tie.
Oh oh, revised that thought....
The lady I posted with the same (ish) hairstyle was in 1872...so that would be second baby...Jane....but the eyebrow and lower lip are still the same as the chappie....
well...to me....
Think I'll go and get a cup or tea.....