Marjery, are you certain William Christian married Rebecca as CROWE? Their 1833 marriage in Ramsey on the IGI is a Church member's contribution which looks invented to "fit" her surname given on the IGI for some children's baptisms.

The extracted entry for son Edward's 1839 bapt has his mother as Rebecca CORKILL.
William Christian & Rebecca CORKILL married in Maughold on 30 Apr 1833, both from Ramsey. Widower & widow.

Rebecca CROW married William Corkill on 28 Oct.1826 in Braddan, and had three children bapt in Ramsey (one born pre-marriage).

I can't find her bapt under Rebecca CROW[E] in either Ramsey or Maughold.

Sue