Miranda Kerr thinks motherhood is a "huge honour".

Miranda Kerr

Miranda Kerr

The 34-year-old model raises son Flynn, six, with ex-husband Orlando Bloom and thinks there's no better feeling than seeing him grow and change, though it also requires a lot of "responsibility".

Asked about the biggest challenge of parenting, she said: "I think it's the responsibility of raising a child to be the best version of themselves. Thinking back, the sleep deprivation for the first year was pretty challenging too! But the sleepless nights were well worth it.

"Being a mother is just a huge honour. My favourite part of the day is picking Flynn up from school. Seeing his little face light up when he sees me! It is joy and love in the purest form. It's just magical seeing him grow and develop his own personality."

Miranda - who is now married to Snapchat founder Evan Spiegel - is trying to "reinforce the basics" of respect and politeness when it comes to raising her little boy.

She said: "At his young age I'm focused on reinforcing the basics- treating everyone with respect and, of course, to have good manners."

The Australian beauty allows herself to indulge "20 percent" of the time, but tries her best to stick with foods "in their most natural state" as much as she can.

She told Red magazine: "I eat foods in their most natural state. I do believe in moderation though and try to live by the 80% fresh and healthy, 20 percent indulgence rule.

"As for exercise, I start the day with at least 20 to 30 minutes of exercise. I like yoga, Pilates, swimming, resistance training, skipping and walking our dog, Teddy. If I have a shoot coming up I target certain specific areas. I just try to keep active and walk as much as possible."