Instead of asking the above question, a more appropriate question is this, “Can my kid get by piano lessons without practice?” The answer is definitely NO.
If you want to learn piano, you must practice. More specifically, you need to practice EVERYDAY. A beginning piano student does not need to practice long hours, but it is very important to establish the habit of practicing everyday. If your kid can have access to a piano outside your house and practice everyday, you may not need a piano at home. For example, if your kid goes to an after school program at a church or a day care center that has a piano and they allow your kid to practice everyday, you may not need a piano at home. Generally speaking, though, you should have a piano at home if your kid is learning piano.