James Tandy East London 1760s

A warm greeting to you all,
I'am seeking help from anyone who can solve this little mystery. I have a marriage certificite JAMES TANDY to JUDITH ELIZEBETH MEAKINS who were married on 16th February 1790, at Bethnal Green.James was a hairdresser by trade and between them they produced 4 girls and 2 boys, one of whom is James junior born 14th June 1788.The mystery is I cannot find a birth record of either James or Judith. Their children were either christianed at St Giles Cripplegate (the eldest two) or St Botolph Without Aldgate.
If this mystery is solved I should
be able obtain his parents etc.
Would be ever so gratefull for an answer.
Regards
Michael