Kiedy jestem rodzicem i kupuje dziecku prezent jak ma isc na urodziny do kolegi :)
It is grammatically correct, but `the' assumes the person you're talking to knows what the gift is, which doesn't make them feel as good as they would if it was a surprise :)
The voice was cut short at prezent, this is quite common and at times I guess at content from previous experience.
Somewhat unrelated to the linguistics, is it true that the concept of giving presents to one's birthday is relatively new (well, like 20 to 30 years or so) in Poland, and was more confined to "imieniny" (nameday) before, and even then, it was more uncommon to give presents? Would be interesting to hear your perspective, dear natives :)
Well, I'm only 27 (ok, closer to 28 now), but I don't know if that's true... what I can say is that imieniny are indeed a lot more important to the generations of may grandparents and parents than they are to young people. Many of them would probably consider them more important than birthday.
But for the younger generations... it's not uncommon for someone to not even remember the date of their imieniny nowadays. When Facebook introduced the option to put this date on your profile, it was really rare for me to see that it's someone's nameday soon. I'm not even sure if the option is still there.