How is に being used in おージャンボにもとーちゃんいたのか?

Question

Slight disclaimer but I have come across some typos in this print of Yotsuba, the manga that this sentence is from. The sentence in question is

おージャンボにもとーちゃんいたのか!

The following sentence is

よつばにもいるよ?

so に's use is the same. I've understood に to be the target particle and も is the inclusion particle. I believe them to be separate in this case and to my knowledge, there is no にも particle. The english translation for the first sentence is "Oh! Jumbo has a daddy too!?" I was wondering what に does here instead of the sentence being something like

ジャンボはとーちゃんもいる。

That also brings me to a side question. In the first sentence, いた was used and the English translation given was as stated before, "Oh! Jumbo has a daddy too!?". Why is いる past tense here? Is the English translation off or perhaps the Japanese? ジャンボ 's dad is alive. I didn't think that warranted a second post, but i'd mainly like to know why に is used here. The closest reason I could think of would be that it is the "target of having" although that still doesn't make sense to me when I think you could just use the non logical particle は。

Thanks for any help that comes my way. It's greatly appreciated.

Answer 1

おージャンボにもとーちゃんいたのか！

This sentence is natural and makes perfect sense. This に is a "location" marker used with いる/ある/ない/etc, although it refers to some abstract "location". You have to get used to this pattern because a verb similar to "to have" is rarely used in Japanese. See: Cases where "に" cannot mean "at" and What is the difference between ni and ni wa, when talking about a person?

• 私には夢があります。
  I have a dream. (literally "There is a dream in me.")
• 彼女には子供が2人います。
  She has two children.
• 彼には才能があります。
  He has a talent.

As for this past tense, it is something called discovery-ta or modal-ta. See: Non conventional usage of the past tense