Sorry, not Donna, but being a busy-body I couldn't resist jumping in!
When you go into Familysearch, select International Genealogy Index.
Type Robert into first name, Callin into last name
Event - select Birth/Christening
Year - type in 1817
Region - choose British Isles
Country - Isle of Man
Click Search - this will bring up 1 record - Robert Callin - Click to view:
This will show an "IGI Individual Record" for
"Robert Callin, Male, Christening date 20 July 1817 in the parish of Patrick, Isle of Man" [Family search always add 'England' but obviously their geography isn't as good as their IT!]
Then it says "Parents: Robt Callin & Jane Kelly"
After that there's a box that says:
Extracted birth or christening record for the locality ...." which means what they've shown was found in the church register. Some entries have "Record submitted by a member of the LDS Church..." or similar in the Messages, which means it could be a guess, correct or otherwise, may or may not have been seen in any register, therefore not to be trusted on its own.
Then, if you go back to the IGI search page, take out Robert Callin's name but put Robert Callin in the father's name boxes and Jane Kelly in the mother's name boxes, choose birth/christening, British Isles, IOM, but leave the year blank, click Search, it will give you a list of 11 children. You will see that the first 7, in the parish of Patrick, IOM, are all extracted from the register so should be pretty reliable, but the other four, in the parish of German, are all 'submitted by members' so perhaps not so trustworthy.
Give it a go and see what I mean. Good luck!