- Stars are located light years apart from each other
- Light year is a measure of the distance light travels in one year
- So, the distance between stars are measured in light years

- The distance between stars are measured in light years
- The sun is a kind of star
- Proxima centauri is a kind of star
- Hence, the distance between the sun and proxima centauri is measured in light years

- "A child is a kind of young human offspring " is not relevant

Hence, the distance between the sun and proxima centauri is measured in light years
The distance between the Sun and the next closest star, Proxima Centauri, is most accurately measured in
- Stars are located light years apart from each other 
- A child is a kind of young human offspring 
- The sun is a kind of star 
- Light year is a measure of the distance light travels in one year 
- Proxima centauri is a kind of star