All the Sites you'll see 

​Natural History museum located at: Cormwell Road, South Kensington, LondonSW7 5BD, United Kingdom. This museum is full of 22 different galleries that are separated into 4 different zones to explore. Some of the 80 million items in this museum date back 4.5 billion years. They have a cafe, restaurant, and a gift shop located in the museum.  The museum is open daily from 10am to 5:50pm entry is free. And they have onsite parking for $10.

St.Paul's Cathedral is located at St.Paul’s Churchyard, London EC4M 8AD, United Kingdom. This is a historically iconic church in London full of beautiful art galleries and history. They offer guided tours and have wheelchair ramps and lifts for accessibility. The hours of operation are monday, tuesday, thursday, friday 8:30am-4:30pm, wednesday 10am-4:30pm, and sunday 8am-6pm. There are no tickets available in advance for June yet but the walk up price for a family of 2 adults and 2 children is $61.55.

Westminster Abbey and the Houses of Parliament are located at: Dean’s Yard, London SW1P 3PA, United Kingdom. This tour will take you to see the beautiful Westminster Abbey, Houses of Parliament, and even Big Ben which is one of London’s most well known treasures. You will have a professional tour guide for the Abbey and you will have an audio guide if you decide to go into the Houses of Parliament. Wheelchair users and their caregiver is free so I just added a ticket for Dad and Brother totaling $165.04.

The London Eye is a world famous ferris wheel that is great for every family.  The London Eye is 443 feet (135 m) tall and it takes 30 minutes to get around the whole thing.  It has been open since 2000 and when it opened it was the worlds tallest ferris wheel.  It is accessible for wheelchair users which is very important to note.  A trip on the london eye is 25.50 pounds which is a very good price for adults, making it 76.50 for the adults and the son, where for Grace it will be 20.50.  In USD it would be $123.

The National Gallery is a great place for all art fanatics, with paintings from the 13th century and up. There isn't an entry fee but booking is recommended. It is wheelchair accessible with the ability to borrow wheelchairs. You can enjoy a meal at their downstairs restaurant named the Ochre. There are also accessibility options for those who are deaf and blind with translators and audio transcripts. 

Kensington Palace (Kensington Gardens, London W8 4PX) similar to Biltmore Estate was the residence of many young royals and Queen Victoria. The Palace is wheelchair accessible and has many rooms to see such as the very room Queen Victoria was born and raised in, the King’s and Queen’s apartment as well as The Jewel Room. Ticket prices are £20.00 for adults (18-64 yrs old), £16.00 for ages 16 &1, and £10.00 for children (5-15 yrs old) for a total price of £66.00 or $83.51usd. The Palace is open Wednesday-Sunday 10 am-6 pm. An eatery known as the Pavilion is also on site. The family should plan on spending 3 hours here.