Marriage
GULLIDGE George 30 years Widower Father unrecorded.
BRIGGS Rose Anne 15 years Single Father unrecorded
12 Jul 1852
At St Mark Penwortham Ade 10/249
Birth
GULLIDGE Selina Ann
1 Apr 1854
Father George GULLIDGE Mother: Rose Ann [Not recorded]
Place not recorded Ade 4/304
I can't see any further records for any of the above in South Australia ie marriage for Selina or deaths for George or Rose Ann.
Do you want a search for Rose's siblings ie possible marriages but may be difficult as Rosa's father's name does not appear on her marriage reg in 1852.
http://www.slsa.sa.gov.au/fh/passengerlists/1848Poictiers.htmThere is a John BRIGGS, wife and five children listed arriving in 1848. Unfortunately no names for children.
Will have a look in the Biographical Index of SA for you.
Cheers
Cando