There were 2 (two) children born and given the name Abraham.
The first younger brother named Abraham de Clercq (1) was christened on 18 May 1670 and died very young, probably before late December 1670.
https://familysearch.org/ark:/61903/1:1:6ZB7-TVV2
This date of death being calculated based on the probable conception date (9 months) being around January 1671 for Abraham de Klerk (2) SV/PROG who was born being on 11 October 1671.
https://familysearch.org/ark:/61903/3:1:3QSQ-G9QJ-34HD