はいっているやら translation difficulty

Hello,

Please help with translation for the second sentence.

「じいさま いえに かえってから あけてくださいね。」
「なかには なにが はいっているやら。」

I guess, I could translate both sentences as

"Old man, since you are returning to home please take it."
"If you open it, there is something within."

But I am not sure about second. I wonder, if I change second sentence to

「なかには なにが はいっていれば。」

Could it change the meaning ?

Thank you very much!

"Old man, please open it when you get home."
"I wonder what is within."

やら is a bit classical sentence final particle similar to ～のだろう（か）.

3 (終助)
文末の言い切りの形に付く。不確かな気持ちをこめて、 自問したり推量したりする時に用いる。

とんぼ釣り、今日はどこまで行った―

いったい何を食わせる―
/quote]
「やら」の検索結果 - Yahoo!辞書

Click to expand...

Thank you very much for your kind explanations and corrections.