Meaning:
“小” means “small,” and “棉袄” means “padded jacket.” This term has been used metaphorically by the Chinese to refer to daughters, who are often considerate and heartwarming, and therefore are compared to a “padded jacket in winter” for parents.
Example:
A: 老李，换新手机了啊？
Lǎo lǐ ，huàn xīn shǒujī le a？
Lao Li, did you just get a new phone?
B: 我说不要，我女儿非要给我买。
Wǒ shuō búyào，wǒ nǚ’r fēi yào gěi wǒ mǎi。
My daughter insisted buying it for me, although I told her I didn’t need one.
A: 你家的小棉袄从小就乖巧懂事。
Nǐ jiā de xiǎomián’ǎo cóngxiǎo jiù guāiqiǎo dǒngshì。
Your daughter has been nice and considerate since she was a kid.