Did Bridget marry? If so, does the record say who her father was?
Have you done all the siblings that you know of for Maria Colgan and Patrick Dyer/Dwyer? And all their children? I have found the county of origin in some unusual places, sometimes the children's death records, or a sibling's record.
the Catholic Parish Registers are at
https://registers.nli.ie/. A quick look did not turn up a Bridget Colgan baptism in Strokestown in 1872.
The informant on her civil birth was Mary Sexton, occupier, of Ashbrook. What do you know about her? Was she related to Maria Colgan? Or she might have been a midwife. Or would it say so, I'm not sure, maybe someone else knows.
Griffith's Valuation of Longford was done in 1855, according to wikipedia. There were no Dyers in Longford. There is only one John Dwyer:
John Dwyer, Longford, Templemichael Parish, renting parcels 71a 71b, house, "offices", yard, and garden from Elizabeth McDonnell
find out what the Catholic parish was for Templemichael Civil Parish, and see if you can find a baptism for Patrick, son of John. But since they are both common given names, it would really help to find a few siblings of Patrick and hopefully find baptism records to match them all - to identify the family a little better.
And don't go just by one census for a estimated year of birth. sometimes the ages are off by 5 years or more from one census to the next.
That's about all I can think of for suggestions.