Does a child (under 16) also have his/her personal allowance?

Does a child (under 16) also have his/her personal allowance (£12,570)? If he or she has interest from savings account more than £100, according to the HMRC website, this interest should be reflected as the income of parent. If a child has his or her own personal allowance, then why it has to be counted as parent's income? I've checked with few tax accountant, their advise is no need to include those savings interest into parent's total income. Is that right? For a child (16 or above), should they submit their own self assessment because only of the interests from savings account? Thank you very much

Hi,
You can see the guidance here:
Interest on savings for children
Thank you.