Simeon Lord's family in England

Simeon Lord is recorded as having six brothers and three sisters.

Generally there appears to be little information about them.

John Lord was born on the 26th April 1765 (Rochdale)
He was baptised on 28 April 1765.
On 14 August 1785 John married Nancy Booth (born 1765) (Rochdale).
John has three children - Edmund (1786-1856), Ann (born 1788) and Mary (born 1792)
He died at Manchester on the 14 October 1801, aged 36 and was buried at St Mary's Todmorden on 15 October 1801.

Mary Lord was born 5 August 1766
She died in 1790 aged 24

Joshua Lord was born on 26 September 1768

Betty Lord was born on 10 April 1773
She died on 6 January 1774 aged almost nine months

Samuel Lord was born 19 November 1774
He died in 1792 aged 18

Thomas Lord born 1776 or 1777

Three other children appear in various lists as being born in 1778
Richard born 12 March and died 30 April

William born 12 March, died 19 March

Sarah born 17 March 1778?
On 27 June 1797 Sarah married John Knowles (1767-1821) at  St Peter (Bradford Cathedral), Bradford, Yorkshire, England.
Sarah died 12 May 1798 aged 20

If the birth dates are correct Richard and William would be twins.
If Sarah was born in 1778 she would also have been born on 17 March. What would the survival rate of triplets be in 1778?

It would be useful to know more about the lives of the brothers and sisters who survived and compare their lives in England with Simeon's experiences in Australia.