にしては

The grammar structure にしては is used to express that something is unexpected or surprising given a certain standard or expectation. It translates to "for," "considering," or "considering that it's…" in English. The speaker is saying that the result or situation does not match what one would normally expect based on the preceding noun or verb.

Basic usage

にしては attaches to a noun or a verb in plain form and introduces a statement that contrasts with expectations.

Here, the speaker acknowledges the standard (first time, being a child) and then states something that goes against what would normally be expected.

With verbs

When used with verbs in plain form, にしては highlights a gap between what the action would suggest and the actual outcome.

Nuance

The key nuance of にしては is that the result doesn't match the expectation – it can be surprisingly good or surprisingly bad. The focus is always on the gap between what is expected and what is actually the case.

Compare with のわりに割に (のわりに), which carries a similar meaning but tends to emphasize degree or proportion more strongly, while にしては focuses more on category or identity (e.g., "for a beginner," "for a professional").