Anders Jonsson is Catharina's illegitimate son, spelled in an old way. ("Henas oag Son)
I can't read everything in front of Catharina's name because it is scribbled, but the + means she died. The comment at the far right (not the far left) says "gift med And. Jansson??? 1800". I don't know if it is the dräng Anders Jansson who she married or another one. Look up marriages for 1800 in the marriage book.
I don't see any Gerta. Do you mean Greta Andersdotter who was born in 1840? She was a lodger (Inh. = inhyses = lodger.)
Anders Jansson born 1861 was a farmhand. (Dr = dräng = farmhand.)
What do you mean when you say Anders is on the birth record of Maria (Maja) born in 1802." Was he "on there" as a father or was he "on there" as a witness to the baptism. Tell us the source.