Sorry - forgot to give the census ref.:
From www.iomfhs.im/lawsons/census/c51-ch.html

CHRISTIAN Robert [age] 26, Ger 2523 203 82
CHRISTIAN Agnes 21 Ger 2523 203 82
CHRISTIAN Andrew 1 Ger 2523 203 82

I have transcripts of the Maughold parish register.
There were a lot of Christian families in Maughold - you would need to confirm from wills if possible - but what you have could fit:
Baptisms:
CHRISTIAN Edward [son of] Mark Christian/ Margaret [no surname] Parish Church [bapt] 1 Apr 1831
CHRISTIAN Elizabeth Mark Christian/ Margaret Kissack Parish Church 8 Jun 1817
CHRISTIAN John Mark Christian/ Margaret Kissack Parish Church 27 Jun 1819
CHRISTIAN William Mark Christian/ Margaret Kissack Parish Church 24 Mar 1822
CHRISTIAN Robert Mark Christian/ Margaret Kissack Parish Church 1 Aug 1824
CHRISTIAN Cath Mark Christian/ Margaret Kissack Parish Church 22 Jul 1827
CHRISTIAN Ann Mark Christian/ Margaret Kissack Parish Church 2 Sep 1833
CHRISTIAN Mark Mark Christian/ Margaret Kissack Parish Church 23 Jul 1837

Mark Christian & Margaret Kissack married 19 Nov 1814 in Maughold.

Mark son of William Christian & Ann Kelly bapt Maughold Parish Church 9 Jan 1785?
Mark CHRISTIAN, 69, Pt y vullin, buried Maughold 21 Feb 1854.

There might be a Maughold M.I. for him, with other stones in the same plot for other family members. (Other family members on MIs are always a huge help when trying to sort out the hundreds of CHRISTIAN entries in the par reg.)

1851 census index:
CHRISTIAN Mark 68 Mau 2524 256 42
CHRISTIAN Mark 13 Mau 2524 256 42
CHRISTIAN Catherine 23 Mau 2524 256 42
CHRISTIAN Margaret 58 Mau 2524 256 42

Sue