What is the ruling of dressing boys in red and yellow?
It is Makrooh-e-Tahreemi for males to wear clothing that is bright yellow in colour. Similarly, it is Makrooh-e-Tanzihi for men to wear red colour clothing. The ruling that applies to adults will apply to children as well (i.e. it will not be permissible to dress male children with red and yellow clothing).
Checked and Approved By:
Mufti Muhammed Saeed Motara Saheb D.B.
(يجب) وظاهر الآية أنه فرض نهر ج ٦ ٥ وكره إلباس الصبي ذهبا أو حريرا ) فإن ما حرم لبسه وشربه حرم إلباسه وإشرابه
Ahsanul Fataawa pg. 62 vol.8
Mahmoodiyya pg.406 vol.27]