Toes point inwards when standing, sitting, or walking. Pigeon toes are also called in-toeing, often caused by genu valgum, or "knock-knee".
Knock-knee can be tagged as knees together feet apart. It's a medical condition that the knees are bent inwards causing the calves to be unaturally spaced out, while the thighs are closer.
So there may be overlap between the two tags, but not all knock-knees show pigeon toes, and not all pigeon toes show knock-knees.
The following tags are aliased to this tag: intoed and pigeon_toes (learn more).