DS1: never (he's 13 now, so pretty sure he never will be bothered) DD: 8 months until never (will never fade, I reckon) DS2: 5/6yo - never (I reckon) DS3: Never will get into them, not really, just the odd moment of play (I reckon, he's only 4 now).
dd1 became attached to a monkey blanket at just under a year, and she still sits chewing it and cuddling her bunny at 6 (7 in March)
dd2 never got attached to a particular soft toy, but has always loved any sort of cuddly, and now sleeps with several on a rotation basis. Her and her friends take them into school to 'talk' to each other (in very squeaky high pitched voices) she is 5 (6 in May)
ds doesn't really 'get' cuddlies, although he likes to stroke tags. he is 2.4
DD has had a huge attachment to her many soft toys - starting around 18 months, now age 7. They all have names and she's devastated if we lose one. They're like her own little family and she makes collars, hats, tiaras, beds for them.
Funnily enough I realised today that DS has got into teddies, well a teddy. He's nearly 18 months and has named a bear (that he's had all his life but ignored up till now) the same name as DSS! He's always had another little soft toy in his cot but tonight insisted it was 'dss bear'!
Dd 2.3 has always had a huge attachment to teddies. She has one that she takes eveywhere and about 30 others that she talks to a plays tea parties etc with. Now she is in a big bed she loves having them all at the end of the bed.
Ds 23mo has 5 that have to go in his cot with him, of which one particular bear is first among equals. He loves this one so much I got scared and bought a spare, but I hope we never have to use it because it looks suspiciously clean and fresh compared to the tatty old original.
DS didn't take any notice of his until he was at least a year+. He grew attached to Iggle Piggle and George Pig plushes first (recognised them off the TV I suppose, not that he watches that much...). Now he's nearly 2 and a half, and loves his teddies, a random plush baby, elmo, noddy, other random ones. Usually has an assortment in bed with him and is quite caring about them.