Name for a child born to older parents long after its siblings

[skippy]

I called my youngest daughter my perfect little surprise, she was born 19 years after my first daughter.
I do like late lamb though, very sweet.

[aghadowey]

Sometimes called 'change of life baby'

[Ayashi]

My grandparents had one daughter, then two years later another daughter, and then seven years later thanks to a whoops they had my mother 

I admit, when I see a sudden child long after the others my suspicions are raised immediately 

[heywood]

As I mentioned and see aghadowey has the same phrase ‘change of life baby’ was one I was aware of.
I remember as a child hearing the expression ‘she had him/her - on the change’. This might be said in a whisper or mimed - a bit like Les Dawson 

[coombs]

Illegitimate grandchild. A late arrival.

[brigidmac]

My foster daughter had two children before her mother had a second child ....
The 18 year old call sometime s calls him uncle tho he.s only 15. !

thru 3 generations  of my ex husband's family ....people had uncles and aunts who were similar ages to themselves .his sister was 20 years younger they called her " la surprise "

[Jean Price]

In New Zealand such a child was referred to as an autumn leaf

Jean

[Bearnan]

My mom and dad had their much wanted second child, another daughter, 18 years after they had me. People sometimes assume a late baby is a mistake, not always! We are lucky to still have our dad who is 96, my sister was in her forties when we lost mom .

The only downside is that my sister didn't know our grandparents ,she has no memory of our paternal grandmother who was the last of the grandparents to die when my sister was three.

[Guy Etchells]

Sometimes the presence of an unmarried daughter of child-bearing age in the household will raise the suspicion that the infant 'sons' and 'daughters' of elderly parents might be illegitimate grandchildren.

Stan

Yes quite so and that must at times happened.

However this suspicion was often the result of the misconception that older people do not engage in sex and it was more acceptable to imagine a late child (of respectable parents) was the result of a wayward daughter than the fact that her parents still engaged in such lewd acts.

Such was the hypocrisy of Victorian attitudes!

Cheers
Guy