Sims 3 keeps freezing randomly for a few seconds (help)

You need to elaborate a little more about this.

1. How big is this new family?
2. Is it a generic game family or is it one self created/one others have created with? Beware of presaved characters saved from other game plays as they may have all sorts of stuff in their inventories. We learned this the hard way with Kirry Bixley Simnel having the entire fruit and veg harvestable contents from one of Rflong7/13's world ...
3. How big is the world you've dumped them in. Come to that, what world have you dumped them in?
4. Is this utilising an old game save in any way? If so, it may have 'bloat' needing cleansed.

In short, there could be any number of reasons that's bringing your poor PC to its knees trying to process what you've opened up, you need to say what you have tried so that by a process of elimination you can find out the cause.

By the way, you may get a faster response putting this query in the Sims 3 Technical Issues section.

There are two sims in the family and one cat which I made in cas

they are in a small made home I didn’t build in costa del sol. I have played in this world before in the same house with even more sims on a less powerful laptop. I have a gaming pc now.

its a new save 

im just confused due to it working fine on an old dying worse gaming laptop but my new powerful pc is having issues. And it wasn’t freezing until around the time I put a bird cage with a bird in the house on the porch.

Sounds like routing issues or corrupted objects somewhere in the neighborhood. If you have Master Controller, reset the whole town and if you have Debug Enabler, click city hall > nraas > debug enabler > city hall options > dumb alarms. It will create script error file to your Sims 3 folder (documents). Open the file with browser and see what it says. If there is a corrupted object it should let you know and you can fix it.

It would be helpful if you could tell which neighborhood this is happening. 

Edit: I just realized you mentioned the neighborhood that is apparently custom made. Routing issues and corrupt objects are very common in these and it is worth resetting the entire neighborhood with Master Control when you start the game.

I apologize I thought costa del sol was the island paradise neighborhood. That’s what I’m playing on. I’ll download those command center mods!

Isla Paradise explains everything. There are routing issues in the neighborhood and you can find easy instructions on how to fix them (no mods needed) in this link: 

https://www.reddit.com/r/Sims3/comments/cf5q7q/a_very_easy_isla_paradiso_lag_fix_no_mods/

I've read that "resetsim" will prevent it from randomly freezing! You could give it a try and see! Good luck!