For some reason my sim Derrick thinks that he has a son named Edward and grandson Trevor, when the only time he ever met Edward was when I had him move in with once to make him playable as they were both originally townies. So how do I remove their family ties in sim Pe and also remove derricks memory met new grandson?

There are two places. In the sim relations tab under the sims own record in Sim Description and in the Family Ties resource - find the family and remove the links. The second one is what shows in the family tree, the first one is the actual linkage between sims which makes them marked as family (so stops romantic interactions for instance). Do you need a picture?

Yes a picture would be great thanks, as I'm not all that great with SimPE

OK

First Pic shows the Sim relationship editing under Sim Description.

1. Find your sim in Sim Description
2. Click on the Relationship tab and find the relevant family with the drop down selector (usually the sim's own family)
3. Click on the sim whose relationship you want to edit (that is the sim with whom you want to change your original sim's relationship) and edit the boxes on the right. There are two places for each box - one is the family setting which is just a tick/check box. With it selected, the sims are set as related/family. The drop down box at the top of the little panel can set the specific relationship - parent, child, sibling, grandparent, aunt, uncle, niece, nephew, cousins. There are two sets of these boxes showing relationships going both ways. So your Sim A and his relationship to Sim B and then Sim B's relationship to Sim A. These don't need to be the same (though usually are). So a parent-child relationship like the one shown would have Sim A (your sim) as the child of Sim B and the recipricol panel would have Sim B as a parent to Sim A.

Commit and save

Second pic shows the relationships for the family tree in Family Ties

1. Select the Family Ties resource
2. Find the relevant family in the drop down box
3. Select the sim you want to edit
4. Pedar is selected in this shot but to change his relationship (in the tree remember) with his mother, you would then have to click on her portrait in the main panel (she would then light up)
5. You edit the relationship here - if you want to remove it altogether just use that remove button. This bit only becomes live when you select the relevant sim in the main panel. Remember selecting Pedar here in the left hand panel selects his relationships to be edited but to change the relationship with his mother (Jenifer) you have to then click on her portrait in the MAIN panel (right) (not the left hand side since what you'd be doing then is selecting her relationships to be edited).

Commit and save


Edit to add:
You mentioned memories too. For this you open up the memory editor in SimPE (let it open fully before you start to edit - watch the loading bar and wait till it's finished). Then select the family and sim in the same sort of way. You will then see the memories in the main panel to be edited. Memories can be edited and deleted at will but there are other things in there which can't be without causing trouble so read on. Memories that you can see in game are in black in the memory editor. Select the memory you want to change - if you want to delete it, then use the 'remove' button while the memory is selected. Commit and save.

Items which are blue and italicised are gossip items. These can be removed (or edited if you want). Green items are inventory items and these can be removed but it's better to do it in game where possible. Leave the grey things alone. These are tokens and various controlling bits of code. You can edit them ... IF YOU KNOW WHAT YOU'RE DOING.

Thank you very much