"אני שמח כי יש לי צעצוע חדש!"

Translation: I am happy because I have a new toy!

[CAA15]

Can you not translate this as "I am happy that I have a new toy!"?
In English, we use that along with because sometimes in sentences like this.

[Pumbush]

אני שמח שיש לי צעצוע חדש

[CAA15]

I see. In this instance though the English use of that is same as because.

[sketchydavid]

I think they have slightly different meanings. In one case you are describing your overall mood, as a result of having the new toy ("because"). In the other case you are describing your specific feelings about having the toy, not your mood in general ("that").

[Theresa754142]

Ani sameakh ki yesh li tsa'atsua khadash!