Emily. I thought I would have a look for you, as I also have COLLETT relatives from that area and time. Sadly, so far, it doesn't look like they are the same family, though I'm sure soemwhere they will be.

However, I did find that the IGI website has plenty of records for you (https://familysearch.org/search/)

I quickly found these:

Baptism:
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George Thomas Collett
baptism/christening date: 20 Aug 1843
baptism/christening place: SAINT LEONARDS,SHOREDITCH,LONDON,ENGLAND
birth date: 15 Oct 1833
father's name: George Daniel Collett
mother's name: Elizabeth

Parents marriage:
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groom's name: George Daniel Collett
bride's name: Elizabeth Orton
marriage date: 17 Jan 1832
marriage place: St. Bride Fleet Street, London, England

Father's baptism:
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name: George Daniel Collett
baptism/christening date: 10 Oct 1824
baptism/christening place: SION CHAPEL-UNION STREET LADY HUNTINGDONS-NC,MILE END OLD TOWN,LONDON,ENGLAND
birth date: 29 May 1812
father's name: Richard Thomas Collett
mother's name: Mary Ann

Grandparent's marriage:
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groom's name: Richard Thos. Collet
bride's name: Mary Ann Heather
marriage date: 25 Mar 1799
marriage place: Saint Bride Fleet St ,London,London,England

Grandfather's baptism:
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name: Richard Thomas Collett
baptism/christening date: 14 May 1768
baptism/christening place: SAINT MARTIN IN THE FIELDS,WESTMINSTER,LONDON,ENGLAND
father's name: Thomas Collett

This should help. I have to say I can't guarantee these are your relatives, but they certainly look likely suspects!