My child still mixes up b and d. Is that a sign of dyslexia?

Flipping b and d, or was and saw, is completely normal in early readers and writers, usually up to around age seven. On its own it is not a reliable sign of dyslexia. It becomes worth a closer look when it lasts well past seven, comes together with slow, effortful sounding out, or shows up alongside trouble hearing the separate sounds inside a word.

When did the reversals settle down for your reader, and what helped: tracing the letters, a b and d hand trick, simply more time reading, or nothing in particular? And if they did not settle, what did you do next?

The fix is rarely more worksheets. It is usually more secure, over-learned letter and sound work, which is the kind of short daily practice we build Lillory around.