*I'm an only child*
Me too Stardust... and my mother's uterine complexities caused her multiple miss-carries ever after... it brought a lot of grief to the marriage which cracked eventually.....
Some years back - it took me an age of delicate questioning - to try and fathom some sense of what transpired while she was carrying me... to term. To say that this is a highly emotive and no go topic for her... would be the ultimate understatement....

Ironically she has blamed my condition 'firmly' on my (deceased) fathers shoulders - claiming that due to her families extreme catholic stance and her upbringing, the chemistry pessaries my father procured early on in their marriage - used to stave off pregnancy - meant for months she wasn't even aware of being pregnant at all... with me!!
Catholics adhering to faith doctrine of the 1950s era you see shouldn't have been having sex for fun/enjoyment at all, contraception was a no go... coitus growing family making (new Catholics) was what it was really all about....
My overall feelings now are that there are a whole host of complexities, disorders, anomalies, mixed dysgenesis and brain-sex imbalances... physical, chromosomal and psychological - all bends that generate a whole colourful rainbow range of options, ticks and quirks....
The scale is very wide and varied....
Do I need AIS as a comfort crutch for what has transpired with me?
No not at all....
But does it go some ways as to help me define and fathom my 'difference' ?
Yes I think it does...
However society and especially religious driven agenda ones... prefers the lie that life strictly = man & woman... male & female
Preferably with the man coming first...