help with identifying vintage boy's size rolex

[penmanila]

hi, all--i've just come into possession of a boy's size "rolex" in rose gold. very clean and runs well, but i'm pretty sure the caseback (which i've yet to open--am away from home and don't have the tools) is a replacement. is anyone familiar with this model and can they tell me about it? one very interesting detail i noticed is a ruby jewel on the tip of the seconds hand. did rolex ever use such an ornament? many thanks, all, for any information and advice. (i'm a complete newbie here--i collect fountain pens and some vintage watches, mostly hamiltons and bulovas, but this will be my first rolex, if indeed it is one.)