I am opening further discussion on Hendrik, because it is possible that this Hendrik (currently given as the husband of Maria and the father of Mijndert) is not the correct person.
Of particular interest is the suggestion that the children of Cornelis Claas /Claesz (Kees de Boer) were known by the patronym CORNELISZ (not CLAASEN)
There are two Hendriks in question.
1) Stamouers.com has Hendrik born 1686 son of Claas Gerrits and Sara van Soloor married Maria BOOIJS. (see entry Hendrik CLAASSEN) He was baptised 6 March 1686 . He had a brother called Meijndert (or Meyndert) and a brother called Gerrit . His half-sister was Hendriette (Henrietta) Wittebol who married W L Wiederhold.
Willem Kempen (Claassens family http://www.kempen.id.au/index.php?id_pag=32) has similar info.
Mansell Upham has this Hendrik married to Maria, and
Delia Robertson (First Fifty Years Project) agrees. http://www.e-family.co.za/ffy/g9/p9571.htm
2)Booysen, Claasen and Buchroeder trees have Hendrik born 1681, the son of Cornelis Claasen and Catharina van Malabar., m Maria Booysen.
HOWEVER, Richard Ball (2010) says that the children of Cornelis Claasen and Catharina van Malabar used the patronym CORNELISZ .(http://www.ballfamilyrecords.co.uk/robberts/I022.html).
So their son was known as Hendrik CORNELISZ although his name is written Hendrik CLAESSEN in the baptismal register.
Ref (Delia Robertson First Fifty Years) http://www.e-family.co.za/ffy/g7/p7266.htm