Maughold parish register has:
Evan Thomas, son of Evan Looney & Margaret Ann bapt Parish Church 30 Nov 1873.

Maughold marriage:
9 Oct 1873
Evan LOONEY, Full age, Bachelor, Farmer, [residence] Magher y Kew, [father] Joseph Looney, Farmer
~and ~
Margaret Ann QUAYLE, Full age, Spinster, [residence] Ballaterson, [father] John Quayle, Farmer.

The Maughold bapts for all Joseph Looney's children were:
LOONEY Sarah daur of Joseph Looney/ Isab Looney Parish Church 11 May 1839
LOONEY John Joseph son of Joseph Looney/ Isab Looney Parish Church 17 Oct 1841
LOONEY Margaret daur of Joseph Looney/ Isab Looney Parish Church 5 May 1844
LOONEY Ewan son of Joseph Looney/ Isab Looney Parish Church 5 Mar 1848
LOONEY Jane daur of Joseph Looney/ Isab Looney Parish Church 27 Aug 1854
LOONEY Robert son of Joseph Looney/ Isabella Parish Church 18 Aug 1850

Joseph Looney & Isabella Looney married in Maughold 21 Oct 1837.

Margaret Ann daur of John Quayle & Isabella was bapt Parish Church 28 May 1849.

Maughold bapts:
QUAYLE Jane Illegitimate daur of John Quayle/ Isab Sayle Parish Church 20 Apr 1834
QUAYLE Cath John Quayle/ Isab Sayle Parish Church 28 Oct 1838
QUAYLE John John Quayle/ Isab Sayle Parish Church 26 Jul 1840
QUAYLE Isab John Quayle/ Isab Sayle Parish Church 22 May 1842
QUAYLE Thomas John Quayle/ Isab Sayle Parish Church 4 Aug 1844
QUAYLE James John Quayle/ Isab Sayle Parish Church 13 Sep 1846
QUAYLE William Henry John Quayle/ Isab Sayle Parish Church 4 Aug 1853
QUAYLE Margaret Ann John Quayle/ Isabella Parish Church 28 May 1849
QUAYLE Edward John Quayle/ Isabella Parish Church 8 Apr 1851.

John Quayle & Isabella Sayle married in Maughold 15 Oct 1837. Isabella had her mother's consent. [Which means that she was under the age of 21.]

Possibly Isabella Anne daur of John Sayle & Margaret Garrett bapt Parish Church 22 Dec 1816, so only a couple of months under age.

You could confirm her age in censuses.

Sue